feat: extend shapefile writer to create .cpg file

Create a new file .cpg which should contain just the text
“UTF-8” together together with the .shp file.

ING-3911

io/plugins/eu.esdihumboldt.hale.io.shp/src/eu/esdihumboldt/hale/io/shp/ShapefileConstants.java

@@ -81,6 +81,12 @@ public interface ShapefileConstants {
 	 * Constant for the shape file extension.
 	 */
 	public static final String SHP_EXTENSION = ".shp";
+
+	/**
+	 * Constant for the CPG file extension.
+	 */
+	public static final String CPG_EXTENSION = ".cpg";
+
 	/**
 	 * Constant for underscore.
 	 */

io/plugins/eu.esdihumboldt.hale.io.shp/src/eu/esdihumboldt/hale/io/shp/writer/ShapefileInstanceWriter.java

@@ -15,10 +15,14 @@
 
 package eu.esdihumboldt.hale.io.shp.writer;
 
+import java.io.BufferedWriter;
 import java.io.File;
+import java.io.FileOutputStream;
 import java.io.IOException;
+import java.io.OutputStreamWriter;
 import java.io.Serializable;
 import java.net.URI;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.FileSystems;
 import java.nio.file.Paths;
 import java.util.ArrayList;
@@ -102,20 +106,27 @@ public boolean isCancelable() {
 	@Override
 	protected IOReport execute(ProgressIndicator progress, IOReporter reporter)
 			throws IOProviderConfigurationException, IOException {
-		progress.begin("Generating Shapefile", ProgressIndicator.UNKNOWN);
+		progress.begin("Generating Shapefile/CPG", ProgressIndicator.UNKNOWN);
 		InstanceCollection instances = getInstances();
 		List<String> filesWritten;
+		List<String> codepagefilesWritten;
 		try {
 			URI location = getTarget().getLocation();
 			String filePath = Paths.get(location).getParent().toString();
 
 			filesWritten = writeInstances(instances, progress, reporter, location);
+			codepagefilesWritten = writeCodePageFiles(filesWritten);
 
-			if (filesWritten.size() > 1) {
-				List<URI> uris = filesWritten.stream().map(f -> {
+			if (filesWritten.size() > 1 && codepagefilesWritten.size() > 1) {
+
+				List<URI> uris = new ArrayList<>();
+
+				for (String f : filesWritten) {
 					File file = new File(filePath + "/" + f + ShapefileConstants.SHP_EXTENSION);
-					return file.toURI();
-				}).collect(Collectors.toList());
+					uris.add(file.toURI());
+					file = new File(filePath + "/" + f + ShapefileConstants.CPG_EXTENSION);
+					uris.add(file.toURI());
+				}
 
 				// Reset the target property so that a caller can find out which
 				// files were created.
@@ -126,7 +137,7 @@ protected IOReport execute(ProgressIndicator progress, IOReporter reporter)
 		} catch (Exception e) {
 			reporter.error(new IOMessageImpl(e.getMessage(), e));
 			reporter.setSuccess(false);
-			reporter.setSummary("Saving instances to Shapefile failed.");
+			reporter.setSummary("Saving instances to Shapefile/CPG failed.");
 		} finally {
 			progress.end();
 		}
@@ -472,6 +483,8 @@ private Map<String, Map<String, ShapefileDataStore>> createSchema(URI location,
 	 * - filename_geometryType.shp if multiple geometries.<br>
 	 * - filename.shp single schema and geom.
 	 * 
+	 * Create the CPG file starting from the Shapefile names
+	 * 
 	 * @param location file location.
 	 * @param numberOfSchemas number of schemas.
 	 * @param schemaEntry current schema in process.
@@ -507,6 +520,8 @@ else if (numberOfGeometries > 1) {
 		File file;
 		try {
 			file = new File(filenameWithType);
+			writeCodePageFile(filenameWithType.replace(ShapefileConstants.SHP_EXTENSION,
+					ShapefileConstants.CPG_EXTENSION));
 		} catch (Exception e) {
 			throw new IllegalArgumentException("Only files are supported as data source", e);
 		}
@@ -724,4 +739,35 @@ private List<String> writeToFile(
 		return filesWritten;
 	}
 
+	/**
+	 * @param filesWritten List of file names that were written (without
+	 *            suffixes)
+	 * 
+	 * @return same list of Files written
+	 * @throws IOException exception in any.
+	 */
+	private List<String> writeCodePageFiles(List<String> filesWritten) throws IOException {
+		for (String filePath : filesWritten) {
+			writeCodePageFile(filePath);
+		}
+		return filesWritten;
+	}
+
+	/**
+	 * 
+	 * 
+	 * @param filePath Path of the file to be written with just one line of the
+	 *            encoding
+	 * @throws IOException exception in any.
+	 */
+	private void writeCodePageFile(String filePath) throws IOException {
+		try (BufferedWriter writer = new BufferedWriter(
+				new OutputStreamWriter(new FileOutputStream(filePath), StandardCharsets.UTF_8))) {
+			writer.write("UTF-8");
+		} catch (IOException e) {
+			throw new IOException("An error occurred while creating/writing the file: filePath "
+					+ e.getMessage());
+		}
+	}
+
 }